Quantum-dot micropillars for parametric THz emission

S. Mariani (Invited author), A. Andronico (Invited author), I. Favero (Invited author), S. Ducci (Invited author), Y. Todorov (Invited author), C. Sirtori (Invited author), M. Kamp (Invited author), J. Claudon (Invited author), J. M. Gérard (Invited author), Tianwu Wang (Invited author), Peter Uhd Jepsen (Invited author), G. Leo (Invited author)

Research output: Contribution to journalConference articleResearchpeer-review


We report on the design, fabrication and optical investigation of AlGaAs microcavities for THz Difference Frequency Generation (DFG) between Whispering Gallery Modes (WGMs), where the pump and DFG wavelengths (λ ≈ 1.3 μm and λ ≈ 75-150 μm, respectively) lie on opposite sides of the Restrahlen band. For the pump modes, we demonstrate CW lasing of quantum-dot layers under electrical injection at room temperature. We control the number of lasing WGMs via vertical notches on the pillars sidewalls, providing a selection mechanism for funneling the power only to the modes contributing to DFG. In parallel with the optimization of the pump lasers and in order to validate design and material parameters before the DFG experiments, we have performed linear measurements on two sets of passive samples. For the telecom range, the micropillars have been integrated with waveguides for distributed coupling and characterized via transmission measurements. In the THz range we have measured reflectivity spectra on 2D arrays of identical cylinders. In both cases, we demonstrate a good agreement between experimental results and simulations. On a more speculative note, we numerically show that etching a hole along the pillar axis can facilitate phase matching, while single-lobe farfield pattern can be obtained for the THz mode by micro-structuring the metallic ground plane around the microcavity. Finally, we suggest a real-time fine-tuning mechanism for the forthcoming active devices.
Original languageEnglish
JournalProceedings of SPIE, the International Society for Optical Engineering
Pages (from-to)86312B
Publication statusPublished - 2013
EventSPIE Photonics West : Quantum Sensing and Nanophotonic Devices X - San Francisco, CA, United States
Duration: 2 Feb 20137 Feb 2013


ConferenceSPIE Photonics West : Quantum Sensing and Nanophotonic Devices X
CountryUnited States
CitySan Francisco, CA

Fingerprint Dive into the research topics of 'Quantum-dot micropillars for parametric THz emission'. Together they form a unique fingerprint.

Cite this